A Flask-based web application designed specifically for astrophotographers, providing essential data for tracking deep-sky objects (DSOs).

• Real-time altitude and azimuth tracking for DSOs
• Visibility forecasts based on altitude, moon illumination, and angular separation
• Integration with Stellarium for live sky visualization
• Customizable imaging opportunity alerts
• Imaging Journal
• Horizon Masking
• Aladin based Framing Assistant

• Python (Flask, AstroPy, Ephem)
• Raspberry Pi compatible
• API integrations (SIMBAD, Stellarium)
• SSO for Multi User installations

Nova helps track Deep Sky Objects (DSOs) positions throughout the night for astrophotography or visual observations.

Nova updates DSOs' positions every minute. Objects marked for special attention are highlighted. It also displays the Moon's illumination and provides graphical insights into the objects' positions throughout the night.

Positions (RA, DEC) are automatically fetched from SIMBAD. Altitude (Alt) and Azimuth (Az) calculations are performed in real time, with updates reflected every minute on the web interface.

In addition it provides information about the angular separation between the objects and the moon, the time they can be imaged and the maximum altitude they reach during this time.

Includes a comprehensive Imaging Journal to log your imaging sessions.

Powerful, interactive framing assistant

When opening Nova, you'll see a list of DSOs sorted by their current altitude (descending order). Objects with project notes are highlighted. You'll also see the date, local time at your selected location, and current Moon illumination. Altitudes above a definable threshold are highlighted in green. If you define a Horizon Mask and there is an obstruction, the field will be colored yellow. Under "Observable" you can find the time in minutes an object is above the altitude threshold (default 20°) and between astronomical dusk and dawn. You can also see the angular separation of the object to the moon.

The main view is organized into three tabs: "Position", "Properties", and "Journal". The first "Position" contains all fields you are used to from the previous versions.

The second tab, "Properties", contains object-specific physical data such as the object's Type, Magnitude, Size, and its Constellation (shown as a three-letter abbreviation).

The third tab, "Outlook" shows the upcoming imaging opportunities for your highlighted objects.

The fourth tab, "Journal" lets you take notes to your imaging sessions.

• Sorting: By default, objects are sorted by descending altitude. You can change sorting by clicking on column headers. Clicking twice reverses the sorting order. Also new in 2.7 is the sorting indicator for every column.

• Searching: Each column header includes a search field allowing filtering. You can combine search terms and use logical operators like < or > for refined filtering. With ! you can exclude content. Nova retains your sorting and filtering choices until you alter them.

• You can now also add multiple phrases in a search field. For example multiple DSO types:

and you can combine filters and sorting from both tabs:

In this example the objects are sorted by maximum observation time. In combination with the filter under "Properties" this shows potential observation time only for the DSO type selected. If you have only a limited view to the sky, for instance because you image from a balcony, you can also set azimuth filters, to focus on objects actually visible to you. Once you set the sorting order and filters, the screen will continue updating every minute, so you can see where the the objects are at any moment. These settings will stay even when switch screens, until you manually reset them.

Nova comes pre-loaded with several DSOs. You can manage (add, remove, or edit) locations and objects from the configuration screen. To add an object, enter its ID and click search. This will trigger a SIMBAD search. If an object was found you can edit its name and project fields and finally add it to your list. All you settings and objects are stored in a single .yaml file which you can find in the main directory. When ever you update your installation, move it to another computer etc, make sure you keep this file (config_default.yaml in single user mode or config_username.yaml in a multiuser setup)

• Object Designations: SIMBAD may not recognize all object IDs. You can however add objects also manually. In that case you need to enter RA and DEC.
• Highlighting Objects: Entering text in the "Notes" field (project in the yaml file) highlights the corresponding object in the main interface. The main purpose is to mark objects you plan to image. In the project field you can put all necessary information, such as the rig you plan to use.

The configuration, including all locations objects and settings, can be downloaded as well as uploaded. When uploading the configuration file it doesnt matter how it is named, it will be automatically renamed to match the user ID (in MUM) or the default name (in SUM)

There is an optional field in locations, where you can define a horizon mask. So if you have certain obstructions at your imaging sites you can configure them there. All calculations will then be based on obstruction free view.

Under the tab "Rigs" you can configure your equipment, configure rigs and calculate the sampling. The rigs configured here can later be selected in the journal.

Since nova now includes more information, the configuration yaml file needs to be updated. After installing the latest version, you can import your previous config yaml file. However - you will notice that the additional fields remain empty if your yaml file was created by a version < 2.7:

What you need to do is to press the "Fetch Missing Details" button. A message will pop up reminding you that this process will take some time.

In order to successfully add the information, your system needs to be connected to the internet. Nova will query multiple catalogs to find the requested information. If you have Stellarium on your computer, you should open it as well - nova will use it as fallback if the search in the various catalogs was not successful.

After pressing "ok" just wait until the page reloads. If everything went well, you can find the additional fields now filled out

Clicking on a DSO in the main list opens detailed graphical information about its nightly position and altitude. These graphics are generated on-demand and might take a few seconds to appear, depending on your computer's performance. You can not only see the current night, but you can select a date you want to see. Just select the day and or month and year and click on "Day". The daily graph also displays a vertical dashed line indicating the meridian transit, which is the point of highest altitude and a crucial time for equatorial mount users to plan for a "meridian flip."

If you click on the button "Find Imaging Opportunities", you will get a list of dates and times when imaging the selected object is possible. From here you can also add the information to your calendar.

In addition, you will also see an approximate fit of your configured rigs.

You can edit the selection criteria for the opportunity search in the configuration settings.

The "Show Framing" button opens a powerful framing assistant.

Nova DSO Tracker also offers the additional possibility to take notes to imaging sessions. On the main screen you can find the Journal at the third tab:

Here you can find all your imaging sessions. If you want to see the detail, click on it and the graph screen for that particular day will open and in addition you will find the session details:

You can add new sessions by clicking the "add new session" button - and filling up the form:

Version 3.3 introduces an optional and anonymous telemetry system to help me understand how the app is used and where to focus development efforts.

• What it is for: It sends a small, anonymous "heartbeat" to help me understand things like which operating systems are most common and if it runs under Docker.
• What it collects: It only sends anonymous aggregate data, such as your app version, OS type (e.g., Windows, Linux), and the counts of your objects, rigs, and locations. (to understand if we run in a bottleneck)
• What it DOES NOT collect: It NEVER sends any personal data, including the names of your objects, your location coordinates, your project notes, or any other sensitive information.
• It is Opt-Out: You can disable this feature at any time on the Configuration -> General page.

The easiest way to install Nova DSO Tracker is via Docker. There is also a video that explains the process.

Alternatively you can of course run it directly in Python:

This guide walks you through setting up your Flask astronomical tracking app, including creating a virtual environment and installing all required dependencies.

Using Homebrew (recommended):

1. Open Terminal.
2. Install Python 3 by running:

brew install python

3. Verify the installation:

python3 --version
pip3 --version

1. Open Terminal.

(Optional) change the directory to where you want the software folder to be installed

2. Clone the repository and open the new directory

git clone https://github.com/mrantonSG/nova_DSO_tracker.git
cd nova_DSO_tracker

A virtual environment keeps your project's dependencies isolated.

1. Create a virtual environment named nova:

python3 -m venv nova

2. Activate the virtual environment:

source nova/bin/activate

Your terminal prompt should now start with (nova).

Install the required Python packages:

pip install Flask numpy pytz ephem PyYAML matplotlib astroquery astropy flask_login python-decouple python-dotenv cerberus ics arrow

(Optional) Verify installed packages:

pip freeze

1. With your virtual environment activated, run:

python nova.py

2. Open your browser and navigate to:

http://localhost:5001

Note: The first startup may take a minute.

When finished, deactivate by running:

deactivate

if you want to close the terminal window, for instance after starting the software on a server, start it like that:

nohup python3 nova.py > app.log 2>&1 &

once you want to later stop it, look for the process:

ps aux | grep python

and stop it:

kill <the number you've found>

Nova supports two user modes:

• Single-user mode: Uses a single configuration file (config_default.yaml). This is the default setting.
• Multi-user mode: Each user has a separate configuration file. Ideal for embedding into external websites where advanced user management is handled externally.

Basic user management is built-in primarily for testing or simple use cases, with user credentials (IDs and passwords) stored securely in the .env file. For integration into a website, it's recommended to handle user management via the website itself.

Additionally, Nova supports a limited guest mode when running in multi-user mode. Guest mode provides automatic access without requiring login credentials, offering a basic overview and limited functionality to give new users a general impression of the app.

To enable multi-user mode, update or add the following line in your .env file:

SINGLE_USER_MODE=False

To revert to single-user mode:

SINGLE_USER_MODE=True

In case you want to have access from various different devices (computers, iPad ...) from within or outside of your home network, you can install it on a server. The software is now optimized to run on a Raspberry Pi5 with good performance. In order to still being able to send objects to Stellarium, please read "stellarium_access_from_server".

For better performance, run Nova with Gunicorn, a lightweight WSGI server. Install it via pip install gunicorn, then start the app using gunicorn -w 4 -b 127.0.0.1:8090 nova:app. This reduces CPU load and improves response times compared to the built-in Flask server.

A pre-built Docker image is available on Docker Hub for easy setup:

View on Docker Hub: mrantonsg/nova-dso-tracker

See the Docker Hub page for instructions on how to run the container.

First step: copy your config yaml to a safe place. You can use the "download configuration" function. After that, replace the files in your nova directory or you do a clean install (recommended) For the clean install you just follow the setup guide. Once all steps are done, copy your config yaml back into the new folder ("upload config") and start the app. Important note: the .env file contains relevant information, especially in multi user mode. It will not be overwritten by a new installation, but if you delete the program folder, it will be deleted as well and you should therefore create a copy of it and place it back once the installation is completed.

Nova DSO Tracker is licensed under the Apache 2.0 License with the Commons Clause. Free for personal, educational, and non-commercial use only. Commercial use requires explicit permission. See LICENSE for full details.

clear skies!